Multi-components measuring and dispensing systems are generally required where several chemical components in liquid form must be individually measured to satisfy a certain predetermined formula. The measurements must be precise and accurate to produce the results desired from the mixture when all of the components are eventually mixed together and to assure that the mixture is the same each time it is made.
An example of such applications are reactive liquid polymers and a catalyst for the production of polymerized solids where not only the amounts but the sequencing of the selected components may be critical. Another application would be the combination of basic colors to produce a certain desired shade of paints or pigments such as those used in coloring concrete In such an application each color component must be precisely measured before mixing to achieve accurate repeatable results.
Today there are equipments available on the market which are intended to achieve the desired results. Some of this equipment is quite good, but also may be complex and expensive to make A typical device uses an electronic weighing cell fitted with a receiving tank where the different components are sequentially introduced and weighed according to a predetermined formula residing in the memory of the controlling electronic circuitry.
The present invention deals with a simpler and more versatile system which achieves the results of prior art equipment at least as accurately but without certain disadvantages inherent in the use of load cells and the complication of the intended apparatus. One such disadvantage has to do with the delivery hose connections that become part of the spring feed back affecting cell calibration. The load cell may also employ a delicate mechanical linkage which is often affected by environmental conditions. Load cell scales, like other scales, are subject to continuing maintenance and relatively easily get out of calibration. Thus the precision of a device employing load cells is difficult to rely upon and requires too much attention.